def show():
    str = "hello world"
    str2 = "test"
    str3 = "python"
    print(f"{str}----{str2}----{str3}")
    print("hello")
    print("world")
    print("python")

show()

def show2():
    for i in range(1,100+1):
         # print(i)
        if is_prime(i):
            print(i, end=",")


def is_prime(n):
    for i in range(2,n):
        if n % i == 0:
            return False
    return True

show2()
print()

num = 100
def show3(a,b):
    global num
    num=num+1
    return a+b,a-b,a*b,a//b

print(show3(10,20))


def fib(n):
    if n <= 2:
        return 1
    return fib(n-1) + fib(n-2)

for i in range(1,20+1):
    print(fib(i),end=",")

def fib2(n):
    a = 1
    b = 1
    for i in range(3,n+1):
        c = a+b
        a = b
        b = c
        print(c,end=",")

